Sectional induction coil



Dec. 4, 1928. 1,694,091

W. H. ADAMS SECTIONAL INDUCTION COIL Fil9d Oct. 13, 1925 2 Sheets-Sheetl Fig. 1.

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Dec. 4, 1928.

W. H. ADAMS SECTIONAL INDUCTION COIL 2 Sheets-Sheet 2 Filed Oct. 15,1925 Invenfon. William H. Adams b MWAYW Patented Dec. 4, 1928.

PATENT OFFICE.

WILLIAM H. ADAMS, OI KENYON, RHODE ISLAND.

SECTION'AL INDUCTION COIL.

Application filed October 13, 1925. Serial No. 62,284.

This invention relates to radio inductance suitable for use in eitherradio receiving or sending circuits, and by means of which undesirableinteraction between different cir- 6 cuits or different parts of thesame circuit due to the external or stray magnetic fields of inductancemay be minimized.

I accomplish the desired object by dividing the inductance coil, as awhole, into structurally independent coil sections, which are connectedin series, each coil section having a fractional part of the totalamount of induction in the coil, and by arranging these coil sectionscoaxially and radially about a common center, so that the field of thecoil is symmetrically disposed in a general circular or doughnut shape.

My invention can be embodied in a single induction coil or in a unitarranged to provide variable inductance or in a coupler.

When thus embodied the two coils of the coupler or the variableinductance will be constructed as above described, with the totalwinding arranged in coil sections and the coil sections of the two coilswill be arranged so that they can be inter-leaved with each other,thereby to produce the variable coupling effect or to give the variableinductance.

In order to give an understanding of my invention I have illustrated inthe drawings some selected embodiments thereof, which will now bedescribed, after which novel features will be pointed out in theappended claims.

In the drawings, Fig. 1 is a view illustrating a vario-coupler embodyingmy invention;

Fig. 2 is an end view showing the movable coil in full lines and thefixed coil in dotted lines;

Fig. 3 is a fragmentary view showing one way of supporting the coilsections;

\ Fig. 4 illustrates how the various coil sections may be formed;

Figs. 5 and 6 are views showing a different embodiment of the inventionand which comprises a primary coil, a secondary coil, and a ticklercoil;

Fig. 7 is a diagrammatic view showing still a different embodiment ofthe invention.

Referring first to Figs. 1, 2 and 3, wherein I have shown avario-coupler embodying my invention, 1 indicates a stationary coil orstator and 2 indicates a movable coil. Each of these coils is made up ofa pluralit of structurally independent coil sections w ich are connectedin series, and which are arranged coaxiall and radially about a commoncenter. T e coil sections of coil 1 are designated as 3 and those ofcoil 2 as 3. The coil sections 3 may be wound in any approved way,either as lain solenoid coils or so-called lattice coils. n theconstruction shown the coil sections are wound in the form of latticecoils, this being preferable because they are in the nature of low losscoils. The inductance of each coil section 3 is a fractional part onlyof the total inductance desired, and since these coils are all connectedin series, a complete coil having the required inductance is produced.The coil sections of each coil are arranged coaxiall and radially abouta common center, as in icated best in Fig. 2. The coil sections 3 of thestationary coil 1 are shown as supported on a stationary support 4 ofinsulating material. This support is shown as having pairs of supportingfingers 5, one pair for each coil section 3, and these fingers areinserted into two of the openings 6 which are formed by the honey-combor lattice structure of the coil section 3. The coil sections3are thusremovable fromthe support 4, and will be held firmly in positionthereon. The support 4 is circular and the pairs of supporting fingers 5are arranged in a circ ular formation, so that when the coil sections 3of the coil 1 are in place they will have the coaxial and radialarrangement illustrated in full lines in Fig. 1 and in dotted lines inFig. 2. As stated above, the coil sections 3 are connected in series, asshown, by the wire sections 7 The coil 1 may be readily formed in thecoil sections, as shown in Fig. 4, by winding each section separatel ona mandrel or support 8, these sections being wound in spaced relation.When one section has been wound, the next section will be started in anadjacent position, but separate from the first section, without breakingthe wire, so that when the sections are completely wound, as shown inFig. 4, they will be connected in series. These connected sectionsmaythen be slipped off from the mandrel or support 8 and arranged in theirradial formation.

A coil such as above described is useful wherever an induction coil isrequired in radio work, and it has the advantage that while it providesthe required inductance yet it reduces to a minimum any undesirableinteraction between different parts of the circuit.

The coils of each coil section may be all in and the componentrespective parts of the various coil sections of the group are severallyconnected in series respectively in their complete circuits of theassembled group.

This invention is also admirably adapted for use in various couplers orvariometers or similar devices. In Figs. 1 and 2, which show a variocoupler, the movable coil 2 is also made with the coil sections, whichare indicated at 3*, and which are connected in series,

as described with reference to the coil sections 3 of the coil 1. Thesecoil sections 3* are shown as supported from a central support 9 and arearranged radially with refer ence to said support. This central support9 is mounted on a rod 10 which is slidable axially through the coil 1.If this device is mounted on a panel 11 of a radio receiving or sendingapparatus, then the support 4 for the coil 1 will be attached to thepanel and the rod 10 carrying the support 9 for the coil 2 will extendthrough the panel and be provided with a knob 12 by which it may beoperated. The coil 2 has the same number of coil sections as the coil 1,and with the arrangement above described the coil sections of the twocoils may be inter-leaved more or less to provide the variable coupling.This interleaving is accomplished by simply moving the stem 10 and knob12 back andiorth, as shown by the full and dotted lines. If the coils 1and 2 are in the same circuit then the device would function as avariometer.

In Fig. 2 the movable coil 2 is illustrated in full lines, while thefixed coil 1 is shown in dotted lines. This Fig. 2, however, illustratesclearly how the coil sections are interleaved.

In Figs. 5 and 6 I have illustrated a different embodiment of theinvention, which comprises three coils each formed of radially arrangedcoil sections, as above described. In this embodiment the three coilsmay constitute the primary coil, the secondary coil, and the ticklercoil of an assembly. The

' coil sections of one coil are indicated at 13,

the coil sections of one of the other coils are indicated at 14, and thecoil sections of the third coil are indicated at 15. The coil sections14 are stationarily mounted, they being supported upon a central fixedsupport 16 and being arranged peripherally of said support and in acoaxial and radial formation.

The coil sections 13 are also arranged in a coaxial and radial formationand are mounted on a swinging annular member 17, which is pivoted at 18to the base 19. The coil sections 15 are also arranged in a coaxial andradial formation and are mounted on a. swinging support 20, which ispivoted at 21 to the base 19. These coil sections are so arrangedrelative to each other that the coil sections 15 and 13 may beinter-leaved with the coil sections 14 and with each other by swingingmovement of the supports 17 and 20.

The relative number of coil sections in each coil may var depending onthe results desired. In the construction shown there are twice as manycoil sections 14 in the stationary coil as there are in each of themovable coils, and the coil sections 13 and 15 are staggered relative toeach other. In this device one ofthe coils may function as a primarycoil, another as the secondary, and the third as the tickler stood ofcourse that the coil sections of each coil. It will be undercoil areconnected in series. The wire connections between the coil sections 14,by which they are thus series-connected, are indicated at 22. Theconnections between the coil sections 13 are indicated at 23 and thosebetween the coil sections 15 at 24.

I have referred above to a construction in which the coil of each coilsection may be divided between different circuits. In Fig. 7 I haveshown diagrammatically such an embodiment of the invention. This Figure7 is a diagrammatic view of one coil section and the turns of the coilsection are divided between the two circuits 31 and 41. One of thesecircuits may be a primary circuit and the other a secondary circuit.

There are various other arrangements which a coil embodying my inventionmay assume, and while I have shown in the drawings two arrangementsmerely to illustrate the principle of the invention, yet I do not wishto be limited thereto, as the invention may be embodied in a widevariety of coils.

I claim:

1. A radio inductance comprising a plurality of coaxial,structurally-independent, series-connected coil sections, each havingafractional part of the total inductance desired, said coil sectionsbeing arranged radially about a common center whereby a magnetic fieldof substantially circular shape is formed.

2. A radio inductance comprising two coils each formed of a plurality ofcoaxial coil sections connected together in series and arranged radiallyabout a common center whereby each coil presents a substantiallycircular magnetic field, the coil sections of each coil beingstructurally inde endent and self-supporting and being spacedsufliciently from each other to permit the coil sections of the othercoil to be interleaved therewith,

and means to move the coils relative to each each other sufficiently topermit their being other. interleaved with the coil sections of another7 3. A radio inductance comprising a coil coil of similar construction.10

formed ofa plurality of coaxial, structurally- In testimony whereof, Ihave signed my 5 independent coil sections connected in series name tothis specification.

and arranged radially about a common center, said coil sections beingspaced from WILLIAM H. ADAMS.

